Two new primateshouse-cat-size, exotically sideburned Titi monkeys
of the genus Callicebushave been discovered in the vast
rain forests of Central and South Central Amazonia.

The discovery was announced on Sunday by Conservation International (CI), a Washington, D.C.-based environmental and research organization. The findings will be published in a study in CI's journal Neotropical Primates.

"Primates are our closest cousins, we share much of their DNA, and we've studied them more than almost any other creature. Yet, we are delighted and surprised by the discovery of these two Titi monkeys," said Russell Mittermeier, president of CI and the study's co-author.

Two new primates, Callicebus stephennashi (above) and C. bernhardi (below), were recently discovered in the Amazon.

In 1963 the Titi monkeys comprised three known species. Now the number has risen to 28.

The new species not only enhance our understanding of primates but also indicate that Amazonia is brimming with flora and fauna yet to be discovered.

"The Amazon rain forest is almost as large as the 48 contiguous states and vast areas remain unexplored," Mittermeier said. The Amazon River basin encourages the evolution of new species with its web of rivers serving as barriersslicing the jungle into island-wedges and isolating species.

Since 1980, 38 species of monkeys have been discovered worldwide, 13 of them in Brazil. "It shows how much we have to learn about the world's largest jungle," said Mittermeier, who has discovered six species of monkey and four species of turtle and is chair of the World Conservation Union's Primate Specialist Group.

The two new Titi monkeys were discovered by Marc van Roosmalen, a Dutch primatologist at the Brazilian National Institute for Amazon Research, in Manaus.

"I didn't realize the Amazon was so poorly known until I started finding all these new animals," van Roosmalen said. Since 1996 he has published accounts of five new species of monkeys. And, his backyard is a jumble of creatures unknown to sciencemonkeys hanging around, waiting to be named and have their lives documented in a scientific journal.

"It has little to do with experience," van Roosmalen said. "I just keep going out into the field and looking for things. Any place I go I find new species." During his quest to find the home of the second smallest monkey, for example, he embarked on seven months of surveys, and discovered eight new species along the way. Van Roosmalen has a reputation for adopting orphan monkeys and occasionally new species are brought to his doorstep.

A local fisherman, for example, delivered the first specimen of one of the two new speciessubsequently named Callicebus stephennashitwo years ago.

The adult female weighed about a pound and a half with a silvery body, a black furry forehead, a crown of silvery-brown, and bright red fluffy sideburns, beard and chest.

Van Roosmalen found the first specimen of the second speciesCallicebus bernhardidead on the forest floor during a survey in 1998. Two live specimens of this monkey were found along the Rio Madeira and kept until they died last year.

Bernhardi monkeys are largely blackish-gray, with dark orange sideburns and chest. The tail is highlighted with a bright white tip.

Mittermeier and van Roosmalen named both of the new speciesa privilege granted to the discoverers. Callicebus stephennashi is named for Stephen Nash, an artist at CI who has contributed to primate conservation though his scientific illustrations.

Callicebus bernhardi is named for the Netherlands' Prince Bernhard, who established the Order of the Golden Ark award to honor conservationists. Both van Roosmalen and Mittermeier have received the Golden Ark.

One of the best ways to find new species is to visit remote villages and check out local pets.

At an annual Indian festival called Quarup, which brings together about 17 Indian tribes, van Roosmalen and Mittermeier watch the wrestling matches, join the festivities and take a look at the village pets, which "gives a cross-section of the local fauna," says Mittermeier.

Often the scientists are able to obtain the pet or at least get directions to where the animal was found. When new species are brought hack to the center in Manaus they are kept in captivity and studied. When the specimen dies, Roosmalen has the skin and skeleton to give to a museum.

"In the last 15 years there has been a boom in the number of new primate discoverieswe now have very dedicated people, like Roosmalen, and we know a lot more about where to look," said Ken Glander, a primatologist at Duke University.

"What is startling is that there are still unexplored jungles on Earth that we know nothing about that are in danger of being destroyed before we know who or what is living there," said Rick Barongi, director of the Houston Zoo.

"These discoveries inspire the explorer in all of us," Barongi said. "To discover a mammal that has eluded identification until the 21st century is very exciting."

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